ArizonaArizona Water Resources Water Resources and Issuesand Issues

Border Governor’s Border Governor’s Conference - Water Conference - Water Table May 8, 2006Table May 8, 2006

Geographic and Socioeconomic Profile

• Area and geographic boundaries– 114,000 sq mi– 6th largest state in U.S.– Bordered on the south by Sonora, on

west by California and Baja California, on north by Utah and on east by New Mexico

– Elevation range 70 feet – 12,633 feet– 51 groundwater basins in Arizona

Geographic and Socioeconomic Profile

• Population– 15 counties; 87 cities and towns– 5.9 million inhabitants (2005)– 2nd fastest growing state in U.S.

• Socioeconomic conditions– Principal activities: manufacturing,

finance, commerce, mining, agriculture, tourism

– 2.9 million employed (4.4% unemployment)

Hydrology

• Climate– Characteristics: warm temperatures, aridity,

seasonal precipitation, high year-to-year variability, strong decade-to-decade persistence

– Average annual rainfall ranges from 3 inches in Yuma to >36 inches along Mogollon Rim

– Average daily temperatures range from mid 90s (F) below 500 feet elevation to the high 50s (F) above 8,000 feet elevation

Average statewide Arizona monthly precipitation, (bars; left-hand scale) and temperature (line; right-hand

scale) 1971-2000

0

0.5

1

1.5

2

2.5

jan feb mar apr may jun jul aug sep oct nov dec

pre

cip

(in

.)

0

20

40

60

80

100

tem

p (

F)

Precip (in.) Temp (F)

Water Supply of ArizonaWater Supply of ArizonaColorado Colorado River 2.8 River 2.8

MAFMAF

Salt Salt River River 0.9 0.9 MAFMAF

Gila River Gila River 0.3 MAF0.3 MAF

GroundwaGroundwater 3.5 ter 3.5 MAFMAF

Hydrology

• Surface Water– Colorado River Water 2.8 maf

• 1.3 maf on River• 1.5 maf Central Arizona Project (CAP) to central Arizona

– Salt and Verde Rivers (Phoenix)• 0.9 maf

– Gila River• 0.3 maf

– Local surface water sources• Little Colorado River, San Pedro River, Upper Verde

River

Hydrology

• Groundwater– Recharge rates vary significantly by area– Deep, productive, good quality aquifers in

many areas of central and southern Arizona– Thin, unproductive, deep or poor quality

aquifers in many systems in northern Arizona (Arsenic, Total Dissolved Solids)

Arizona Water SupplyArizona Water SupplyAnnual Water BudgetAnnual Water Budget

Water SourceWater Source Million Acre-Feet Million Acre-Feet (maf)(maf)

% of Total% of Total

SURFACE SURFACE WATERWATER

Colorado RiverColorado River 2.82.8 36.4 %36.4 %CAPCAP 1.61.6 21%21%

On-RiverOn-River 1.21.2 16%16%

In-State RiversIn-State Rivers 1.21.2 15.6%15.6% Salt-VerdeSalt-Verde 0.90.9 12%12%

Gila & othersGila & others 0.30.3 4%4%

GROUNDWATEGROUNDWATERR

3.53.5 45.5%45.5%

EFFLUENTEFFLUENT 0.180.18 2.3%2.3%

TotalTotal

7.7 maf7.7 maf

Arizona Reservoirs & Arizona Reservoirs & CapacityCapacity

Reservoir Capacity (million AF)

Lake Powell 24.5

Lake Mead 25.9

Lake Mohave 1.8

Lake Havasu 0.65

Lake Pleasant 0.81

Horseshoe Lake 0.13

Bartlett Lake 0.18

Roosevelt Lake 1.6

San Carlos Lake 1.3

Apache Lake 0.25

Canyon Lake 0.06

Saguaro Lake 0.07

Alamo Lake 1.05

Reservoir Capacity

58.3 MAF

Arizona mean, high capacity and low capacity reservoir levels from 1971 through 2005, expressed

in percent of total reservoir capacity

Reservoir Name

Average

Capacity

HighCapacit

y

HighCapacit

yYear

LowCapacit

y(2004)

Colorado River System Lake Powell

70% 98% 1983 31%(2005)

Colorado River System Lake Mead

77% 98% 1983 51%

Colorado River SystemLake Mohave

89% 92% 2003 91%

Colorado River System Lake Havasu

92% 94% 1995 91%

Verde River Basin System56% 91% 1992 43%

Salt River Basin System59% 77% 1979 43%

Sources: ADWR, UofA, USGS

DemandDemand

Industrial .41 maf

5%

Agriculture5.9 maf

77%

Municipal 1.37 maf

18%

Border Profile

• Two thirds of Arizona’s border is under federal jurisdiction as national monuments, forests, wildlife refuges, bombing ranges or are tribal lands

• Significant agricultural and urban water use is therefore restricted to area near Yuma and to the communities of Nogales, Sierra Vista and Douglas

Border ProfileGroundwater Basin

2003 Populati

on

2003Surface Water

Demand (acre-ft)

2003Groundwa

ter Demand(acre-ft)

2050 Populatio

n

Yuma 176,000 788,000 304,000 502,000

Santa Cruz AMA

37,000 20,000 58,500(2025)

Upper San Pedro

82,000 4,500 34,000 110,000

Douglas 28,500 0 95,000 36,500

Yuma BasinCultural Water Demand-2003

• 1.09 million acre-feet used in 2003 by agricultural, municipal and industrial sector– Well pumpage and diversion of Colorado River

contract water– 96% Agricultural Use

• Use not expected to increase• 72% surface water

– 3.5% Municipal Use• Rapidly growing communities of San Luis, Yuma and

Fortuna Foothills• 85% surface water

– .5% Industrial Use• 69% surface water

GROUNDWATER DATA FOR THE YUMA BASIN (DRAFT)

Basin Area, in square miles: 792

Major Aquifer(s):Name and/or Geologic Units

Basin Fill

Well Yields, in gal/min:

Range 3,186-5,271 Median 5,098 (3 well reported)

Measured by ADWR and/or USGS

Range 10-7,000 Median 2,456

(327 wells reported )

Reported on registration forms for large (> 10-inch) diameter wells

Range 500-3,000 ADWR (1990)

Range 0-2,500 USGS (1994)

Estimated Natural Recharge, in acre-feet/year:

213,000 Freethey and Anderson (1986)

Estimated Water Currently in Storage, in acre-feet:

49,000,000 (to 1,200 ft bls) ADWR (1994)

34,000,0001 (to 1,200 ft bls) Freethey and Anderson (1986)

35,000,000 (to 1,200 ft bls) Arizona Water Commission (1975)

Current Number of Index Wells: 11

Date of Last Water-level Sweep: 1992 (587 wells measured)

Reported Water Quality Exceedences:Arsenic, Cadmium, Fluoride, Lead, Nitrate, Organics, Solids, and Trace

Elements (Antimony, Beryllium, and Thallium)

1Predevelopment Estimatebls=below land surface

Santa Cruz AMA

• 37,000 people; population concentrated in Nogales and along the Santa Cruz River

• Large fluctuations in temporary residents

• Nogales, AZ population 23,000

• Nogales, Mexico population 300,000

Nogales

Tubac

PIMA

COUNTY

Rio Rico

SANTA

CRUZ

COUNTY

Amado

Demographics

Santa Cruz AMA Demand

25,800 AF

10,300 AF

7,300 AF

1,500 AF

537 AF

8,600 AF

All water uses

Upper San Pedro BasinCultural Water Demand - 2003

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

Municipal Industrial Agricultural

Water Use Sector

Acr

e-F

eet

Surface water

Groundwater

Douglas BasinCultural Water Demand - 2003

• 60,400 acre feet of groundwater• Irrigation Non-expansion area

– Most of basin is an Irrigation Non-expansion area

– no new lands can be irrigated with groundwater

• 89% Agricultural Use– Water use is increasing

• 11% Municipal Use– Demand is increasing slowly

“Subflow” subsurface water subject to surface water law

Laws governing surface water are distinct from those governing groundwater

Government Framework and Management of Water

Resources

– Surface water• Prior appropriation doctrine

– “First in time, first in right”

– Groundwater• Beneficial use doctrine

– Unlimited ability to pump, so long as use is “beneficial” and “reasonable” (outside AMAs)

– Ability to pump constrained by system of rights and permits (inside AMAs)

Government Framework and Management of Water

Resources• Federal Agencies

– Bureau of Reclamation• Administers Colorado River Basin Project Act and

Colorado River Contracts.• Responsible for construction of major water supply

development projects– Environmental Protection Agency

• Federal oversight of surface water and drinking water quality programs

• Oversight of state efforts to regulate solid waste landfills and hazardous waste sites

– Army Corp of Engineers• Conducts flood control studies and dam, levee and

channelization projects. Regulates placement of dredged or fill material into waters of the U.S.

Government Framework and Management of Water

Resources• State of Arizona Agencies

– Arizona Department of Water Resources• Groundwater management and administration of water

rights• Technical and administrative support to the surface

water adjudication court• Authority to consult, advise and cooperate with the U.S.

Secretary of Interior on certain matters related to the Colorado River

• Supervision of safety of dams under state jurisdiction– Arizona Department of Environmental Quality

• Administers water pollution control, monitoring and assessment, and contamination site cleanup programs

• Effluent reuse, groundwater recharge projects and discharge of water to aquifers or streambeds must meet water quality standards

Government Framework and Management of Water

Resources• State of Arizona Agencies

– Central Arizona Water Conservation District

• Tax-levying public improvement district of the state responsible for Central Arizona Project system maintenance and operations, repayment obligations and creation of water resource management programs

– Arizona Water Banking Authority• Stores Arizona’s unused Colorado River allotment in

groundwater basins to firm up urban water supplies for Arizona to be used during times of shortages on the Colorado River or during CAP service interruptions.

• May enter into interstate agreements with entities in Nevada and California to store water in Arizona

Government Framework and Management of Water

Resources• Local Agencies

– Have certain authorities to obtain and manage water resources locally in accordance with state and federal laws

– Public water utilities• Set water rates, can enact local water conservation

and water use ordinances. For example, can require effluent use on golf courses, time of day lawn watering, etc.

– Private water utilities• Regulated by the Arizona Corporation Commission,

which regulates water rates and authorizes curtailment tariffs when demand is greater than production

• Cannot pass ordinances affecting water use or rates

• There are different programs and regulations in Active Management Areas (AMAs), Irrigation Non-Expansion areas (INAs) and in areas outside of AMAs and INAs.

• Statewide, all wells must be registered and drilled by a licensed well driller

• Statewide, transportation of groundwater between groundwater basins is prohibited except as allowed specifically by statute

Groundwater Groundwater ManagementManagement

Water Management AreasWater Management Areas

Joseph City INA: No new irrigated

lands

Prescott AMA goal: safe-

yield by 2025

Phoenix AMA goal: safe-

yield by 2025

Tucson AMA goal: safe-

yield by 2025

Harquahala INA: No new irrigated

lands

Douglas INA: No new

irrigated lands

Pinal AMA goals:- allow development

of non-irrigation uses

- preserve agriculture as long

as feasibleSanta Cruz AMA goal:- maintain safe-yield- prevent decline of water table

• 1980 Groundwater Management Act:– Established Active Management Areas (AMA’s) –

Currently 5– Established a system of groundwater rights based on

historic use and permits for new uses subject to specific conditions

– Set long-range water management goals for AMAs• Will AMAs achieve their goals? What other actions are

needed?• Requires management plan for each AMA

– Created the Arizona Department of Water Resources to administer the provisions of the Act

• Department has regulatory, permitting and enforcement power; it does not control water supplies or infrastructure

Groundwater Groundwater Management – Management –

Active Management AreasActive Management Areas

Groundwater Management –

AMA Management Plans– New plan every 10 years,

though 2025; developed through a public process

– Increasingly stringent conservation requirements

– Include long-range water demand and supply projections

– Conservation programs for agriculture, municipal and industrial water users

– Recharge/augmentation program and water quality assessment

• Irrigation non-expansion areas– Established in areas of critical

groundwater overdraft-but not as severe as in AMAs

– Prohibition of new agricultural irrigation acreage

– Management objective to protect existing water users

– 3 INAs: Douglas, Harquahala, Joseph City

Groundwater Groundwater Management – Irrigation Management – Irrigation

Non-Expansion AreasNon-Expansion Areas

• Underground Storage– CAP and effluentCAP and effluent– 55 Active Permits55 Active Permits– Permitted volumes 150 af to 200 Permitted volumes 150 af to 200

kaf/yearkaf/year– Most recharge facilities are located Most recharge facilities are located

within AMAs; especially the Phoenix AMAwithin AMAs; especially the Phoenix AMA

• Conservation• Reuse• Augmentation

Challenges: Future Water Challenges: Future Water SuppliesSupplies

Future Water SuppliesFuture Water SuppliesUnderground Storage - BenefitsUnderground Storage - Benefits

• Long-term storageLong-term storage

• Large capacityLarge capacity

• Little evaporative Little evaporative lossloss

• Reduces risk of Reduces risk of subsidencesubsidence

Future Water Supplies-Future Water Supplies-ConservationConservation

• Public outreach:Public outreach:• Teach Good Water Habits Statewide Teach Good Water Habits Statewide • Provide information on the best available Provide information on the best available

conservation technologiesconservation technologies• Provide incentives – tax creditsProvide incentives – tax credits• Voluntary local conservation goalsVoluntary local conservation goals• Promote low water use designs in landscapingPromote low water use designs in landscaping

• Local government initiatives:Local government initiatives:• ‘‘Toilet to tap’ Toilet to tap’ • Domestic/commercial water-harvesting and use Domestic/commercial water-harvesting and use

of ‘graywater’of ‘graywater’• Encourage water-efficient appliances, fixtures, Encourage water-efficient appliances, fixtures,

ordinancesordinances• Ordinances for use of effluent for large turf Ordinances for use of effluent for large turf

areas such as golf courses, parks and sports areas such as golf courses, parks and sports facilitiesfacilities

Future Water Supplies - Effluent Future Water Supplies - Effluent Reuse and AugmentationReuse and Augmentation

• Improve treatment quality or match quality to useImprove treatment quality or match quality to use

• Turf and Landscape Uses - some municipal and Turf and Landscape Uses - some municipal and county ordinances require effluent for new golf county ordinances require effluent for new golf courses and turf areas. There are also regulatory courses and turf areas. There are also regulatory incentivesincentives

• Recharge excess for later recoveryRecharge excess for later recovery

• Direct Reuse – considered but must overcome Direct Reuse – considered but must overcome public perception issuespublic perception issues

• Augmentation includes importing water where Augmentation includes importing water where legally available, cloud seeding, constructing legally available, cloud seeding, constructing necessary infrastructure, securing water sources necessary infrastructure, securing water sources and rights, desalinationand rights, desalination

Challenges: Indian Water Challenges: Indian Water SettlementsSettlements

• 28% of Arizona Land held in Trust for the 28% of Arizona Land held in Trust for the benefit of Native Americansbenefit of Native Americans

• Many areas of the state are affected by Many areas of the state are affected by Indian Water Rights settlements with Indian Water Rights settlements with significant implications for water significant implications for water management and access to watermanagement and access to water

• Recently Settled:Recently Settled:– Gila River Indian Community and Tohono Gila River Indian Community and Tohono

O’odhamO’odham635,000 acre-feet/year to Gila River Indian 635,000 acre-feet/year to Gila River Indian

CommunityCommunity-- Fort Yuma – Quechan-- Fort Yuma – Quechan

• Pending settlements; Navajo, Hopi, White Pending settlements; Navajo, Hopi, White Mountain Apache and San Carlos ApacheMountain Apache and San Carlos Apache

Challenges - Surface Water Challenges - Surface Water AdjudicationsAdjudications

Gila RiverGila River

Little Colorado Little Colorado RiverRiver

Definition: “A general stream Definition: “A general stream adjudication is a judicial adjudication is a judicial proceeding in which the nature, proceeding in which the nature, extent, and relative priority of extent, and relative priority of water rights is determined.” water rights is determined.”

•Court must define the legal Court must define the legal difference between surface difference between surface water and ground water water and ground water before rights can be before rights can be determineddetermined

Gila & Little Colorado cases are still Gila & Little Colorado cases are still in Phase 1 after 30+ yearsin Phase 1 after 30+ years

Challenges - Colorado RiverChallenges - Colorado River

• Of the 7.5 million acre-feet of water Of the 7.5 million acre-feet of water available to the lower basin states, available to the lower basin states, Arizona’s Central Arizona Project water Arizona’s Central Arizona Project water supply has the most junior priority.supply has the most junior priority.

• River is over-allocatedRiver is over-allocated• 16.5 maf allocation vs. 13 - 15 maf actual16.5 maf allocation vs. 13 - 15 maf actual

• Drought impacts on water supplyDrought impacts on water supply• Discussions are underway on supply Discussions are underway on supply

augmentation, conservation and augmentation, conservation and system management to meet demands system management to meet demands and obligationsand obligations

Upper Basin (7.5 Upper Basin (7.5 mafmaf)

Lower Basin (7.5 Lower Basin (7.5 maf)maf)

California – 4.4 mafCalifornia – 4.4 maf

Arizona – 2.8 mafArizona – 2.8 maf

Nevada – 0.3 mafNevada – 0.3 maf

Mexico 1.5 Mexico 1.5 mafmaf

ArizonArizona a

Upper Upper Basin Basin – 50 – 50 kafkaf

Lee Lee FerryFerry

Colorado River Colorado River Compact & Treaty Compact & Treaty

AllocationsAllocations

Mexican Water Treaty of Mexican Water Treaty of 19441944

Allots to Mexico 1.5 maf of Allots to Mexico 1.5 maf of Colorado River water per Colorado River water per year, plus 200,000 acre-year, plus 200,000 acre-feet if the Secretary feet if the Secretary determines that surplus determines that surplus

water is available.water is available.

Colorado River FlowsColorado River Flows

Estimated past flow averages

8

10

12

14

16

18

Million A

cre

Feet

Legally allocated

16.5 MAFTree rings,

Upper Basin (1512-1961)

13.5 MAF

Tree rings, Upper Basin (1512-2000)

14.7 MAFIsotopes,

Delta clams (1500-1950) 12.5 MAF

Lowest 20-year average(1579-1598) 10.95 MAF

• Arizona Drought Preparedness Plan adopted in 2004 to identify drought impacts, prepare drought response and reduce drought impacts

• Water providers must prepare drought plans

• Drought monitoring is ongoing

Challenges -DroughtChallenges -Drought

Average water year (October –September) temperature and total water-year precipitation in Arizona from 1930-2002.

Figure Author: Ben Crawford, CLIMAS

• Issues related to the Colorado River are under federal jurisdiction and international treaty

• Increasing population growth is impacting shared and limited water supplies

• Limited hydrologic information for many border basins hinders water planning and management

• Water quality issues in the Douglas/Agua Prieta and Ambos Nogales pose a threat to local water supplies

• Lack of access to renewable water supplies to support increasing demand

Challenges - BorderChallenges - Border

• Need for an integrated binational groundwater model to effectively manage the Santa Cruz AMA water resources to meet the management goal

• Uncertainty about the future use of effluent generated by Mexico and treated at the Nogales International Wastewater treatment plant in Arizona and concerns about the quality of the effluent. Effluent is an important supply for riparian areas and groundwater recharge

Challenges - BorderChallenges - Border